Haemodynamic shock continues to be a frequent cause of severe morbidity and mortality. Insufficient blood supply to the essential organs: the brain, heart, kidneys and the digestive system causes organ failure with rapid functional deterioration and, if not treated, irreversible damage. Shock is caused by either reduction of blood volume, or by inappropriate dilatation of the blood vessels. The result of both conditions is a discrepancy between the blood volume and the vascular volume, leading to a fall in blood flow and pressure. The ultimate treatment of shock is directed toward restoring normal blood volume-vascular volume relationship. This treatment usually requires care by skilled medical personnel in an appropriately equipped facility. These therapeutic measures can only be successful if irreversible damage to the essential organs has been prevented during the time from the onset of shock. This can be achieved by diverting blood and directing blood flow away from the tissues that can withstand prolonged lack of blood supply such as the muscles, bones and skin to the essential organs.
Blood diversion is also applied frequently by orthopedic surgeons during operative procedures on the legs and arms. This is achieved by applying a tight bandage to a limb that is to be operated on and then by inflating a pneumatic cuff to a pressure of approximately 250 mm Hg at the proximal end of the limb to create a ‘bloodless’ surgical field.
Another aspect of blood diversion is the use of tight support stockings, support hoses, or elastic sleeves to prevent undesired pooling of blood in the veins (normal and varicose) of the lower extremities. This application is focused at limiting the volume of the deep and superficial veins, which may cause venous stasis of blood resulting in intra-vascular clotting leading to superficial or deep-vein thrombosis. The pressure needed to compress the veins is substantially lower than that needed for arterial draining and blocking and ranges from 20 to 60 mm of Hg. Likewise, it is often desired to apply to an ailing, injured or burned limb a tight tubular elastic bandage that is coated with a medicated cream, jelly or ointment for treatment of the injury, skin illness or burn. This tubular bandage must be in tight contact with the skin surface for best clinical results of the treatment.
The treatment for shock disclosed in U.S. Pat. No. 4,848,324 includes an elastic long sleeve that is rolled upon itself to create a toroidal compressive ring that may be rolled up onto a limb to displace its blood toward the central circulation.